1. Field of the Invention
The present invention relates to a visual information processing device which is capable of processing speed information (optical flow) for an object moving at high speed.
2. Description of the Related Art
FIG. 1 shows a three-dimensional resistance circuit network 1 for processing an optical flow, as presented, for example, in ["Neural Computer", Berlin, (1988), p.101, C. Koch, et al]. Shown in the figure are a variable power supply 2, a capacitor 3, a variable resistor 4, connecting points 5 and 6 of the three-dimensional resistance circuit network 1, a resistor 7 for connecting the points of an upper layer and an under layer, a variable resistor 8 for connecting the points in an upper layer surface (or an under layer surface), and a switch 9 connected to the resistor 8.
Next, the operation will be explained. The voltage of the variable power supply 2, the value of the variable resistor 4, and the value of the variable resistor 8 for connecting the points, which are determined from input data obtained from photoelectric conversion devices such as photodiodes, are simultaneously input to the connecting points of the three-dimensional resistance circuit network at a certain time interval. The variations in the voltage at the connecting points 5 and 6 resulting from a variation in an optical signal, caused by the movement of an object, disturbs the circuit network system. The three-dimensional resistance circuit network then enters a new, stable state of minimum power consumption in accordance with Kirchoff's law. From the voltage value of each of the connecting points 5 and 6 which have reached a stable state, two-dimensional speed vectors in the x and y directions can be determined. In this case, however, since the contour of the object becomes unclear, the switch 9 is provided so that a contour can be formed at a rational position.
A conventional visual information processing device has been constructed as mentioned above. As a result, the following problems exist in that the construction of a three-dimensional resistance network in an integrated circuit is difficult and the formation of photoelectric conversion devices such as CCDs, photodiode arrays or the like in the same information processing device is also difficult.